© 2007-2009 Bob Hackett, Sander Kingsepp and Peter Cundall
Revision 1
15 May 1922:
Tokyo. Laid down at Ishikawajima shipyard as a WAKATAKE-Class
destroyer and designated No. 22.
14 April 1923:
Launched and numbered D-12.
21 May 1924:
Completed.
1 August 1928:
Renamed YUGAO.
1 November 1929:
Lt (Vice Admiral, posthumously) Aruga Kosaku (45) assumes command.
30 November 1929:
Lt Aruga is promoted LtCdr.
1 December 1930:
An unknown officer assumes command.
15 January 1934:
LtCdr (Rear Admiral, posthumously) Kenma Isogu (48) (former CO of W-5, W-13) assumes command.
15 November 1934:
An unknown officer assumes command.
1939:
One of three Kampon boilers is removed reducing speed to 18
knots. 25mm AA guns and depth charge racks and throwers are fitted for 60 DCs.
Extra ballast is added to compensate for the loss of topside weight and to
increase stability. The changes increase her displacement to 910-tons.
1 April 1940:
Reclassified as a special duty patrol boat and
renumbered 46.
5 March 1941:
PB-46 becomes temporary flagship of the Kure Guard Unit.
29 November 1942:
PB-46 departs Moji escorting the “D” convoy (No. 8 Military Movement) consisting of KURAMASAN and KENKOKU MARUs.
30 November 1942:
Arrives at Saeki.
13 December 1942:
Arrives at Rabaul.
14 February 1943:
A fire breaks out at Kure Navy Yard, causing damage to PB-46 and torpedo boat HATO.
20 April 1943:
At 0600, departs Saeki, Kyushu, escorting convoy No. 420 consisting of ONOE, KINKASAN, and KOYU MARUs.
28 April 1943:
At 1440, arrives at Palau.
2 May 1943:
At 0650, departs Palau escorting convoy No. P-502 consisting of MITAKESAN, MYOKO, MUKO, NISSHO and MYOGI MARUs.
9 May 1943:
About noon, auxiliary minesweeper TAKUNAN MARU No. 3 joins the escort.
10 May 1943:
At 1145, arrives at Saeki.
2 June 1943:
At 0800, PB-46 departs Saeki for Palau escorting convoy O-204 consisting of GENOA, SEIZAN and KEIZAN MARUs.
11 June 1943:
NW of Palau. At about 0950, in squall conditions, LtCdr (later Vice Admiral) John A. Tyree’s USS FINBACK (SS-230) attacks the convoy. Tyree fires three torpedoes and gets at least one hit in GENOA MARU’s forward in No. 1 hold. PB-46 counterattacks, but fails to inflict damage, and FINBACK escapes. GENOA MARU continues to progressively flood forward until 1730, when Abandon Ship is ordered. At 1851, she sinks by the bow at 07-35N, 143-28E. At 1158, the remainder of convoy O-204 arrives at Palau.
19 June 1943:
At 0545, departs Palau in convoy To-906 consisting of DELAGOA, DAINICHI, KAZAN, MACASSAR, SAN FRANCISCO MARUs and EIKO MARU No. 2, escorted by PB-46 and minesweeper W-17.
E20 June 1943:
At latitude 10N, W17 is detached and returns to Palau.
28 June 1943:
At 1920, arrives at Saeki.
E 10 July 1943:
At latitude 29N, PB-46 and minesweeper W-18 join the escort of convoy O-806 that departed Saeki on 8 July consisting of fleet supply ship ARASAKI and ASO, EHIME, KAZAN and ZUISHO MARUs escorted by auxiliary gunboat HINO MARU No. 5.
16 July 1943:
At 1200, the convoy, except straggler KAZAN MARU, arrives at Palau.
20 July 1943:
At 1200, PB-46 departs Palau with minesweeper W-17 escorting convoy FU-006 consisting of ERIE, KINKASAN, KENZAN, KAMO and INARI MARUs.
E 21 July 1943:
At latitude 10N, W-17 and probably PB-46 are detached to return to Palau.
25 July 1943:
At 1345, PB-46 departs Palau escorting convoy FU-506 consisting of SHOKO, HIBI, KOYO, YURI, KOFUKU and MUKO MARUs.
2 August 1946:
At 1800, arrives Saeki.
29 July 1943:
At 1500, arrives at Fukashima, Japan.
12 August 1943:
At 0730, PB-46 departs Saeki for Palau with subchaser CH-11, auxiliary minesweepers TAMA MARU and TAKUNAN MARU No. 3 escorting convoy O-208 consisting of HIBI, MATSUE (SHOKO), YASUKUNI, MOJI, FUKKAI, YASUSHIMA, SHICHISEI and UMEKAWA MARUs. At latitude 29N, TAKUNAN MARU and TAMA MARU No. 3 are detached to return to Saeki.
21 August 1943:
Arrives at Palau.
26 August 1943:
At 0700, PB-46 departs Palau for Ujina with auxiliary gunboat KAZAN MARU escorting convoy FU-407 consisting of empty troop ships BRAZIL, FUKKO, HAVRE, YAMATO, TOHO and MINRYO MARUS. LtCdr John A. Scott's USS TUNNY (SS-282) makes several attacks on the convoy, but is unsuccessful, probably due to defective Mark 14 torpedoes of which Scott fires 11. TUNNY is depth charged, damaged and after a fire breaks out aboard, forced to abort her war patrol.
3 September 1943:
Arrives at Fukashima, then departs.
4 September 1943:
Arrives at Ujina.
14 November 1943:
At 1200, convoy No. 4114 consisting of UDO, NIKKO, CHIYO and HOKKO MARUs escorted by destroyer YUZUKI, kaibokan FUKUE and PB-46 departs Truk. HOKKO MARU is towing damaged subchaser CH-10.
19 November 1943:
NE of Asuncion Island, Northern Marianas. In the early morning hours, Cdr (MOH, posthumously) Samuel Dealey's USS HARDER (SS-257) makes radar contact off the port quarter of the convoy. Dealey attempts to contact two other boats of his wolfpack, USS PARGO (SS-264) and SNOOK (SS-279), but all radio frequencies are jammed by the Japanese. Dealey makes an "end-around" then submerges 15,000 yards ahead of the convoy. HARDER is detected by YUZUKI’s sonar before Dealey's crew can work out a good solution and Dealey has to snap-shoot to avoid being rammed by one of the transports. At 0415 (JST), 5,384-ton HOKKO MARU is hit. At 0435, she sinks at 22-27N, 147-15E. Dealey swings HARDER around and fires his four stern tubes. At 0435, UDO MARU is hit and badly damaged. [2]
YUZUKI takes UDO MARU in tow, but at 1040, the transport's hull splits and the aft part of the ship sinks. CHIYO MARU takes up towing CH-10 and heads for Chichi-Jima with FUKUE. Later, NIKKO MARU is ordered back to assist in the tow of UDO MARU. At 1850, NIKKO MARU arrives back on the scene, but experiences great difficulty trying to tow UDO MARU. Finally, the wreck is abandoned and sinks a few hours later.
The escorts counterattack and drive HARDER deep under a thermocline layer of colder water. Dealey's crew counts 64 depth depth charges dropped over the next five hours during which time they reload all tubes. HARDER surfaces early in the afternoon and takes up the chase again. That night, Dealey closes to within 1,000 yards of the convoy. He fires four Mark 14-3A steam torpedoes at a transport, but they all run deep and pass under the target. Dealey makes another end-around and submerges 12,000 yards ahead of the convoy. He sets up and at 2355, fires three bow torpedoes and gets two hits, one amidships and another in NIKKO MARU's stern.
20 November 1943:
The Japanese get all NIKKO MARU's pumps running and efficiently control the flooding. In the early morning hours, HARDER fires five more torpedoes at her, but all miss. NIKKO MARU maneuvers so that she can comb the wake before the third one is fired. The last torpedo makes a circular run, forcing HARDER to submerge to prevent her being hit.
Dealey attempts to battle-surface on NIKKO MARU, but the merchant finds the range first and straddles HARDER, forcing her down again. Out of torpedoes a frustrated Sam Dealey departs the area, but later, NIKKO MARU loses her battle with the sea and sinks.
USN codebreakers intercept and decrypt a message from the captain of Patrol Boat PB-46 that reads:“At 0900, HOKKO MARU sank in position 23-42 N, 140- (?) E.”
At 1540, USN codebreakers intercept and decrypt a message from an unknown station that says, “YUZUKI will proceed to Yokouska and undergo repairs.”
27 November 1943:
Arrives at Yokosuka.
2 December 1943:
At 0600, PB-46 departs Chichi-Jima for Yokosuka with minesweeper W-28 escorting a convoy consisting of SANKISAN and HINODE MARUs.
4 December 1943:
Tokyo Bay. Arrives at Tateyama.
5-6 December 1943:
At 2350, departs Tateyama. Arrives at Yokosuka.
11 December 1943:
At 1000, PB-46 departs Yokosuka with kaibokan OKI and subchaser CH-31 escorting convoy No. 3211A consisting of MITAKESAN and HAKOZAKI MARUs.
14 December 1943:
HAKOZAKI MARU is detached for Chichi-Jima with engine trouble.
20 December 1943:
At 0800, the convoy arrives at Truk.
10 January 1944:
At 0700, departs Yokohama for Owase with SAISHU MARU Nos. 6 and 7 escorting convoy No. 7110 consisting of KOGYO, MISHIMA, TAIRYU MARU and an unidentified freighter.
12 January 1944:
S of Daio Zaki, Honshu. At about 2300, LtCdr (later Rear Admiral) William B. Sieglaff's USS TAUTOG (SS-199) attacks the convoy at 34-10N, 136-55E. Sieglaff torpedoes and damages KOGYO MARU that takes on a list to port. The Ise Bay Guard Unit dispatches several subchasers to the area to intercept the submarine.
13 January 1944:
After 0003, PB-46 conducts a depth-charge attack against an underwater target, then takes KOGYO MARU under tow.
14 January 1944:
Returns to Owase Bay.
20 May 1944:
PB-46 is reassigned to the Yokosuka Naval District’s 3rd
Surface Escort Division.
10 November 1944:
SW of Cape Iro. At about 1000, LtCdr John D.
Gerwick’s USS GREENLING (SS213) torpedoes and sinks PB-46 at 34-30N, 138-34E.
10 January 1945:
Removed from the Navy List.
Author's Notes:
[1] No data were found detailing PB-46's movements during April 1940-April 1943. Readers with access to such data are requested to post the information on on the Discussion
& Questions board or the IJN Ship Message Board.
[2] Some of HARDER's "hits" may have actually been duds.
-Bob Hackett, Sander Kingsepp and Peter Cundall
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